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* [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host
@ 2011-12-14  6:37 Sasha Levin
  2011-12-14  6:37 ` [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD Sasha Levin
  2011-12-15  4:25 ` [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Matt Evans
  0 siblings, 2 replies; 4+ messages in thread
From: Sasha Levin @ 2011-12-14  6:37 UTC (permalink / raw)
  To: penberg; +Cc: mingo, gorcunov, asias.hejun, kvm, matt, Sasha Levin

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
 tools/kvm/include/kvm/kvm.h |    2 ++
 tools/kvm/kvm.c             |    5 +++++
 2 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/tools/kvm/include/kvm/kvm.h b/tools/kvm/include/kvm/kvm.h
index 7159952..d24b70a 100644
--- a/tools/kvm/include/kvm/kvm.h
+++ b/tools/kvm/include/kvm/kvm.h
@@ -79,4 +79,6 @@ static inline void *guest_flat_to_host(struct kvm *kvm, unsigned long offset)
 	return kvm->ram_start + offset;
 }
 
+bool kvm__has_cap(struct kvm *kvm, u32 cap);
+
 #endif /* KVM__KVM_H */
diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c
index 35ca2c5..a2f7a89 100644
--- a/tools/kvm/kvm.c
+++ b/tools/kvm/kvm.c
@@ -517,3 +517,8 @@ void kvm__notify_paused(void)
 	mutex_lock(&pause_lock);
 	mutex_unlock(&pause_lock);
 }
+
+bool kvm__has_cap(struct kvm *kvm, u32 cap)
+{
+	return ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, cap) == 0;
+}
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD
  2011-12-14  6:37 [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Sasha Levin
@ 2011-12-14  6:37 ` Sasha Levin
  2011-12-15  0:52   ` Matt Evans
  2011-12-15  4:25 ` [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Matt Evans
  1 sibling, 1 reply; 4+ messages in thread
From: Sasha Levin @ 2011-12-14  6:37 UTC (permalink / raw)
  To: penberg; +Cc: mingo, gorcunov, asias.hejun, kvm, matt, Sasha Levin

Check KVM_CAP_IOEVENTFD before using ioeventfds.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
 tools/kvm/builtin-run.c           |    2 +-
 tools/kvm/include/kvm/ioeventfd.h |    2 +-
 tools/kvm/ioeventfd.c             |   16 +++++++++++++++-
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/tools/kvm/builtin-run.c b/tools/kvm/builtin-run.c
index 76f1a8c..47e4ea8 100644
--- a/tools/kvm/builtin-run.c
+++ b/tools/kvm/builtin-run.c
@@ -932,7 +932,7 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
 
 	kvm->single_step = single_step;
 
-	ioeventfd__init();
+	ioeventfd__init(kvm);
 
 	max_cpus = kvm__max_cpus(kvm);
 	recommended_cpus = kvm__recommended_cpus(kvm);
diff --git a/tools/kvm/include/kvm/ioeventfd.h b/tools/kvm/include/kvm/ioeventfd.h
index df01750..3a95788 100644
--- a/tools/kvm/include/kvm/ioeventfd.h
+++ b/tools/kvm/include/kvm/ioeventfd.h
@@ -19,7 +19,7 @@ struct ioevent {
 	struct list_head	list;
 };
 
-void ioeventfd__init(void);
+void ioeventfd__init(struct kvm *kvm);
 void ioeventfd__start(void);
 void ioeventfd__add_event(struct ioevent *ioevent);
 void ioeventfd__del_event(u64 addr, u64 datamatch);
diff --git a/tools/kvm/ioeventfd.c b/tools/kvm/ioeventfd.c
index 3a240e4..75dd3f2 100644
--- a/tools/kvm/ioeventfd.c
+++ b/tools/kvm/ioeventfd.c
@@ -18,9 +18,14 @@
 static struct	epoll_event events[IOEVENTFD_MAX_EVENTS];
 static int	epoll_fd;
 static LIST_HEAD(used_ioevents);
+static bool	ioeventfd_avail;
 
-void ioeventfd__init(void)
+void ioeventfd__init(struct kvm *kvm)
 {
+	ioeventfd_avail = kvm__has_cap(kvm, KVM_CAP_IOEVENTFD);
+	if (!ioeventfd_avail)
+		return;
+
 	epoll_fd = epoll_create(IOEVENTFD_MAX_EVENTS);
 	if (epoll_fd < 0)
 		die("Failed creating epoll fd");
@@ -33,6 +38,9 @@ void ioeventfd__add_event(struct ioevent *ioevent)
 	struct ioevent *new_ioevent;
 	int event;
 
+	if (!ioeventfd_avail)
+		return;
+
 	new_ioevent = malloc(sizeof(*new_ioevent));
 	if (new_ioevent == NULL)
 		die("Failed allocating memory for new ioevent");
@@ -68,6 +76,9 @@ void ioeventfd__del_event(u64 addr, u64 datamatch)
 	struct ioevent *ioevent;
 	u8 found = 0;
 
+	if (!ioeventfd_avail)
+		return;
+
 	list_for_each_entry(ioevent, &used_ioevents, list) {
 		if (ioevent->io_addr == addr) {
 			found = 1;
@@ -123,6 +134,9 @@ void ioeventfd__start(void)
 {
 	pthread_t thread;
 
+	if (!ioeventfd_avail)
+		return;
+
 	if (pthread_create(&thread, NULL, ioeventfd__thread, NULL) != 0)
 		die("Failed starting ioeventfd thread");
 }
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD
  2011-12-14  6:37 ` [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD Sasha Levin
@ 2011-12-15  0:52   ` Matt Evans
  0 siblings, 0 replies; 4+ messages in thread
From: Matt Evans @ 2011-12-15  0:52 UTC (permalink / raw)
  To: Sasha Levin; +Cc: penberg, mingo, gorcunov, asias.hejun, kvm

On 14/12/11 17:37, Sasha Levin wrote:
> Check KVM_CAP_IOEVENTFD before using ioeventfds.
> 
> Signed-off-by: Sasha Levin <levinsasha928@gmail.com>

A much nicer solution than my "[PATCH V2 2/2] kvm tools: Make virtio-pci's
ioeventfd__add_event() fall back gracefully if ioeventfds unavailable".

 matt.nastyhacks--;

Acked-by: Matt Evans <matt@ozlabs.org>

> ---
>  tools/kvm/builtin-run.c           |    2 +-
>  tools/kvm/include/kvm/ioeventfd.h |    2 +-
>  tools/kvm/ioeventfd.c             |   16 +++++++++++++++-
>  3 files changed, 17 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/kvm/builtin-run.c b/tools/kvm/builtin-run.c
> index 76f1a8c..47e4ea8 100644
> --- a/tools/kvm/builtin-run.c
> +++ b/tools/kvm/builtin-run.c
> @@ -932,7 +932,7 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
>  
>  	kvm->single_step = single_step;
>  
> -	ioeventfd__init();
> +	ioeventfd__init(kvm);
>  
>  	max_cpus = kvm__max_cpus(kvm);
>  	recommended_cpus = kvm__recommended_cpus(kvm);
> diff --git a/tools/kvm/include/kvm/ioeventfd.h b/tools/kvm/include/kvm/ioeventfd.h
> index df01750..3a95788 100644
> --- a/tools/kvm/include/kvm/ioeventfd.h
> +++ b/tools/kvm/include/kvm/ioeventfd.h
> @@ -19,7 +19,7 @@ struct ioevent {
>  	struct list_head	list;
>  };
>  
> -void ioeventfd__init(void);
> +void ioeventfd__init(struct kvm *kvm);
>  void ioeventfd__start(void);
>  void ioeventfd__add_event(struct ioevent *ioevent);
>  void ioeventfd__del_event(u64 addr, u64 datamatch);
> diff --git a/tools/kvm/ioeventfd.c b/tools/kvm/ioeventfd.c
> index 3a240e4..75dd3f2 100644
> --- a/tools/kvm/ioeventfd.c
> +++ b/tools/kvm/ioeventfd.c
> @@ -18,9 +18,14 @@
>  static struct	epoll_event events[IOEVENTFD_MAX_EVENTS];
>  static int	epoll_fd;
>  static LIST_HEAD(used_ioevents);
> +static bool	ioeventfd_avail;
>  
> -void ioeventfd__init(void)
> +void ioeventfd__init(struct kvm *kvm)
>  {
> +	ioeventfd_avail = kvm__has_cap(kvm, KVM_CAP_IOEVENTFD);
> +	if (!ioeventfd_avail)
> +		return;
> +
>  	epoll_fd = epoll_create(IOEVENTFD_MAX_EVENTS);
>  	if (epoll_fd < 0)
>  		die("Failed creating epoll fd");
> @@ -33,6 +38,9 @@ void ioeventfd__add_event(struct ioevent *ioevent)
>  	struct ioevent *new_ioevent;
>  	int event;
>  
> +	if (!ioeventfd_avail)
> +		return;
> +
>  	new_ioevent = malloc(sizeof(*new_ioevent));
>  	if (new_ioevent == NULL)
>  		die("Failed allocating memory for new ioevent");
> @@ -68,6 +76,9 @@ void ioeventfd__del_event(u64 addr, u64 datamatch)
>  	struct ioevent *ioevent;
>  	u8 found = 0;
>  
> +	if (!ioeventfd_avail)
> +		return;
> +
>  	list_for_each_entry(ioevent, &used_ioevents, list) {
>  		if (ioevent->io_addr == addr) {
>  			found = 1;
> @@ -123,6 +134,9 @@ void ioeventfd__start(void)
>  {
>  	pthread_t thread;
>  
> +	if (!ioeventfd_avail)
> +		return;
> +
>  	if (pthread_create(&thread, NULL, ioeventfd__thread, NULL) != 0)
>  		die("Failed starting ioeventfd thread");
>  }


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host
  2011-12-14  6:37 [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Sasha Levin
  2011-12-14  6:37 ` [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD Sasha Levin
@ 2011-12-15  4:25 ` Matt Evans
  1 sibling, 0 replies; 4+ messages in thread
From: Matt Evans @ 2011-12-15  4:25 UTC (permalink / raw)
  To: Sasha Levin; +Cc: penberg, mingo, gorcunov, asias.hejun, kvm

On 14/12/11 17:37, Sasha Levin wrote:
> Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
> ---
>  tools/kvm/include/kvm/kvm.h |    2 ++
>  tools/kvm/kvm.c             |    5 +++++
>  2 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/tools/kvm/include/kvm/kvm.h b/tools/kvm/include/kvm/kvm.h
> index 7159952..d24b70a 100644
> --- a/tools/kvm/include/kvm/kvm.h
> +++ b/tools/kvm/include/kvm/kvm.h
> @@ -79,4 +79,6 @@ static inline void *guest_flat_to_host(struct kvm *kvm, unsigned long offset)
>  	return kvm->ram_start + offset;
>  }
>  
> +bool kvm__has_cap(struct kvm *kvm, u32 cap);
> +
>  #endif /* KVM__KVM_H */
> diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c
> index 35ca2c5..a2f7a89 100644
> --- a/tools/kvm/kvm.c
> +++ b/tools/kvm/kvm.c
> @@ -517,3 +517,8 @@ void kvm__notify_paused(void)
>  	mutex_lock(&pause_lock);
>  	mutex_unlock(&pause_lock);
>  }
> +
> +bool kvm__has_cap(struct kvm *kvm, u32 cap)
> +{
> +	return ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, cap) == 0;
> +}
                                                            ^^^^

D'oh, this needs to be != 0, not == 0.


Cheers,


Matt

---

From: Matt Evans <matt@ozlabs.org>
Date: Thu, 15 Dec 2011 15:19:47 +1100
Subject: [PATCH] kvm tools: Fix inverted logic bug in kvm__has_cap

Commit 42efb1abf4ebebeedd14af34c073e673923e2898 compared KVM_CHECK_EXTENSION's
result wrong, stating 'has cap' true if 0.  Invert the comparison.

Signed-off-by: Matt Evans <matt@ozlabs.org>
---
 tools/kvm/kvm.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c
index 9583ab2..25f1419 100644
--- a/tools/kvm/kvm.c
+++ b/tools/kvm/kvm.c
@@ -523,5 +523,5 @@ void kvm__notify_paused(void)
 
 bool kvm__has_cap(struct kvm *kvm, u32 cap)
 {
-	return ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, cap) == 0;
+	return ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, cap) != 0;
 }
-- 
1.7.0.4


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2011-12-15  4:24 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2011-12-14  6:37 [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Sasha Levin
2011-12-14  6:37 ` [PATCH 2/2] kvm tools: Don't use ioeventfds if no KVM_CAP_IOEVENTFD Sasha Levin
2011-12-15  0:52   ` Matt Evans
2011-12-15  4:25 ` [PATCH 1/2] kvm tools: Add kvm__has_cap() to check whether a cap is available on the host Matt Evans

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